Via: Toby Scott
Preheat the oven to 180°C/gas mark 4. Wipe the rhubarb stalks clean and cut into 7.5cm-long pieces. Cut any thicker stems in half lengthways. Put in a large shallow roasting tray and scatter over the lemon zest and juice and the sugar. Cover with foil and bake for 30 mins until tender.
Remove the rhubarb from the oven, uncover and carefully pour the cooking juices into a small pan. Boil rapidly for 3-4 mins until slightly syrupy. When cool, pour back over the rhubarb and set aside.
For the pancakes, sift the flour, baking powder and a pinch of salt into a mixing bowl, then add the sugar. Make a well in the middle and add the egg yolks, ricotta, buttermilk, milk and 25g of the melted butter. Whisk together to make a smooth batter.
In a separate bowl, whisk the egg whites into soft peaks then gently fold them into the batter.
Heat a large non-stick frying pan over a medium heat. Brush with some of the remaining melted butter. Add 3 large spoonfuls of the batter, spaced apart, and cook for 2 mins until golden brown underneath and bubbles start to appear on top. Flip and cook for 1-2 mins more. Serve in batches as you cook them or put them on a plate, then cover with a clean tea towel and keep warm in a low oven while you cook the rest. You should get 18 pancakes.
Serve 3 pancakes per person on warmed plates, topped with some of the roasted rhubarb, a dollop of Greek-style natural yoghurt and the seeds of half a passion fruit.